Actually this might be the problem. Do you by any chance have dual graphics? If you do make sure game uses the correct (dedicated) one. If you don't, then I'm afraid some choppynes is to be expected... unless you are willing to lower the ingame settings, depriving yourself of the neath's beauty cruelly.edited by Pan Tofel on 2/14/2017

Are you playing on a laptop? If you are, chances that you indeed have dual graphic are quite high. Anyway download this: http://www.techspot.com/downloads/4895-msi-afterburner.html . It's primary an overclocking utility (you won't need this) but also a reliable way to find out details about your cards. Run it and you should be able to see how many GPUs you have. Go to setting to see which card is which, I think they are gonna be labeled just as &quotGPU1/GPU2&quot on the main screen.

If you find you have two cards, run Sunless Sea while also having the MSI Afterburner running and check which GPU is active while you play. (Note you should actually play for a few minutes and check retrospectively as mere returning to windows screen can switch the active GPU)edited by Pan Tofel on 2/15/2017

Note that if all the above tips don't help, you should send a support ticket to sunlesssea@failbettergames.com (attach an affected savefile and your system information).

Choppy framerates were a big problem for many players directly after the game was released, but the problem has been fixed long since. The devs would probably want to know about anyone still encountering it...